To quote Maurice Chevalier in the 1958 movie musical Gigi (currently getting a stage revival on Broadway): “Thank heaven for little girls!” Only let’s change that to, “Thank heaven for Kate Besworth’s little girls!” The Shaw Festival actress may be 27 years old, but she can still play underage like nobody’s business.

The frizzy-haired Besworth was a dizzying delight as Thomasina Coverly, the teenage math genius, in the Shaw’s revival of Arcadia two seasons ago—a production that, remounted by Mirvish at the Royal Alex, just won a Toronto Theatre Critics’ Award. And she’s no less charming as the plucky young heroine of Peter and the Starcatcher, the fabulous new Shaw family show that’s already shaping up to be one this year’s big hits.

The fact that Besworth’s Molly is the show’s central character tells you a lot about this spoofy but affectionate prequel to Peter Pan. Oh, Peter’s here, all right—as a moody and initially nameless orphan—but the nascent Boy Who Wouldn’t Grow Up doesn’t come into his own until the second act. Before then, it’s Molly’s story. Rick Elice’s play—adapted from Dave Barry and Ridley Pearson’s kids’ novel, Peter and the Starcatchers—is female-empowering as well as laugh-out-loud funny. It serves as a long-desired antidote to those revivals of J.M. Barrie’s classic in which adult audiences cringe as Peter and the boys get to go off on adventures while maternal Wendy stays behind and plays house.

As Pan fans know, Barrie wrote his own origin story, the whimsical Peter Pan in Kensington Gardens, which was published as a sort-of prequel in 1906, two years after his play’s smash debut. Starcatcher, however, offers a humorous alternative fiction in the style of Wicked, tailored for modern audiences. Here, Peter-to-be (Charlie Gallant) is no more than a surly, abused lad and it’s Molly, the unusually gifted daughter of a British lord, who ends up introducing him to heroism and magic—after she discovers the boy and two other luckless orphans in the hold of a ship during a sea voyage.

The ship, auspiciously christened Neverland, is one of two bound for the island of Rundoon, where Molly’s dad, Lord Aster (Patrick Galligan), has been charged with delivering a chest full of treasure on behalf of Queen Victoria. But pirates commandeer his ship, the Wasp, and proceed to chase down the Neverland. The pirate captain is the mad, malapropism-afflicted Black Stache (Martin Happer), so named for his ebony-hued cookie duster. He’s a dedicated villain destined to gain a nemesis in Peter but lose a body part in the process. (And if there’s any doubt this is the future Captain Hook, consider that his first mate is a scallywag known as Smee.)

The musical play, which opened on Broadway in 2012 and flew off with five Tony Awards, is rollicking, ridiculous fun for all ages. There are daring feats of bravery and delicious bits of slapstick. There are smelly-fart jokes for the kids and Mary Martin jokes for the theatre geeks. There’s an acrobatic mermaid (Jenny L. Wright), a helpful porpoise (Kelly Wong), and a flying cat. And the whole rough-and-tumble thing is loosely knitted together with jolly songs by Elice and Wayne Barker (Dame Edna’s accompanist—say no more).

The play uses a framing device in which the story is told by a troupe of actors with no set and makeshift props. Director Jackie Maxwell obliges with an exuberantly inventive “backstage” staging, in which designer Judith Bowden furnishes ropes, trunks, ladders, and other paraphernalia found in the wings of a Victorian-era theatre. (The festival’s century-old Royal George is the perfect venue for this show.) Maxwell’s dozen-strong cast, meanwhile, performs as if happily stuck partway between a Victorian melodrama and a Christmas panto.

The juiciest of the hams include Happer’s quirky Stache, Jonathan Tan’s eye-rolling Smee, and Billy Lake as an island chief who speaks in a private language made up of Italian culinary terms. Wright is equally impressive whether dangling from silks as the sage mermaid Teacher, or spouting endless alliterations as Molly’s nanny, Mrs. Bumbrake—a randy lady who finds shipboard romance with the malodorous sailor Alf (Shawn Wright).

Besworth’s clever, athletic Molly, meanwhile, provides a perfect role model for young girls. But anyone crushing on the actress should know that the onstage spark between her character and Gallant’s handsome Peter is authentic—offstage, the two are a couple and engaged to be married later this season.

Reviewing a 1986 revival of Sweet Charity, then-New York Times critic Frank Rich called it “a tired-businessman’s entertainment.” And looking at it now, in Morris Panych’s Mad Men–flavoured production for the Shaw, you can imagine this would be the kind of mid-1960s Broadway musical that Megan would drag Don Draper to see after a hard day at the ad agency.

Certainly, philandering Don would get a kick out of the show’s title character, Charity Hope Valentine (Julie Martell), a naive and eternally hopeful Times Square taxi dancer. She’s just the kind of willing gal he’d have a brief fling with before dumping her—something that happens repeatedly to poor Charity in the course of the story.

Inspired by Federico Fellini’s 1957 neo-realist film Nights of Cabiria (in which the heroine, played by the lovable Giulietta Masina, was an Italian sex worker), Sweet Charity has never been more than a minor musical with a few sharp and sassy numbers by Cy Coleman and Dorothy Fields—”Big Spender,” “If My Friends Could See Me Now”—and some classic Bob Fosse choreography. Fosse turned it into a mediocre 1969 film with Shirley MacLaine that should be seen if only as a reminder that, long before she played cranky old ladies, MacLaine was one kick-ass song-and-dance star.

Martell, who looks less like Shirley and more like the young Barbra Streisand, has a winsome manner and a crooked smile to match Charity’s cockeyed optimism. She also swings her handbag with such carefree abandon that it becomes a danger to passersby. But she doesn’t elicit our pity at her character’s self-delusion or our admiration at her resilience. The production’s most effective song, in fact, isn’t even one of hers. It’s “Baby, Dream Your Dream,” sung by the excellent Kimberley Rampersad and Melanie Phillipson as Charity’s cynical fellow dancers—a wry tune in which they begin by mocking their friend’s middle-class suburban fantasies, then admit to finding them appealing as well.

Ken MacDonald’s subway-themed set is impressive, if somewhat sterile; Parker Esse’s choreography evokes signature Fosse (while going easy on the “jazz hands”); and Charlotte Dean’s nifty ’60s costumes run the gamut from square to groovy. The show looks and feels like a well-preserved relic. Perhaps, after Peter Hinton’s radical and much-derided treatment of Cabaret last season, Panych felt he had to play it safe. But Cabaret is a great musical that didn’t need to be reinterpreted; Sweet Charity, a lesser and less-seen work, could use some bold ideas or a fresh perspective. Instead, it’s been allowed to remain an amusing, undemanding entertainment that would set Don Draper’s toe tapping without ever bothering his conscience.